底排参数对底部排气弹弹道特性的影响

为研究不同底排条件下底部排气弹的弹道特性，探讨了底排药剂燃烧和减阻机理，建立了底排内弹道和外弹道模型，分析了底排装置结构参数和药剂燃速系数等对底部排气弹减阻增程效果的影响；结果表明：一定范围内药柱长度的增加能显著提高增程率，但药柱长度过长会由于燃气的引射作用降低增程率；减小药柱内径和增大喷口直径可以提高底部排气弹增程率；分瓣数的增加对提高增程率有较大作用，但应考虑对工程实现的影响；研究范围内存在最优药柱长度和燃速系数；总阻减阻率随着底排工作时间总是经历一个先增大后减小的过程。

Effects of Base-Bleed Parameters on Ballistic Characteristics of Base-Bleed Projectile

To study ballistic characteristics of base-bleed projectile under different base-bleed conditions, the mechanism of base-bleed grain combustion and drag decrease were discussed.Then the model of interi-or ballistics and exterior ballistics of base-bleed projectile was established and used to analyze influence of the structure parameters and combustion rate coefficient of base-bleed unit on range-increase and drag-de-crease effects of base-bleed projectile.Results show that,the diminution of grain inner diameter,the aug-mentaion of grain length,section number and nozzle diameter can help to increase the range-increase rate in a certain range,but the influence on engineering realization should be considered;there is a best grain length and combustion rate coefficient in certain range,and the total drag-decrease rate increases firstly and then decreases with time goes.